Just wanted to add, the one name that could be decent, is Roy Oswalt. With their front three and the emergence of Worley, they probably won't pick up Oswalt's option.
I wouldn't mind a two year deal for Oswalt. I dont necessarily expect the 2010 Oswalt, but he's still a solid veteran that would help us now, and likely will not require a long term contract. Two years would allow us to move him at either trade deadline but even if he stayed for two years, he'd be up for FA again, just as Purke, Meyer and Solis(and potentially Cole/Ray) are ready to make their mark at the big league level.
Strasburg, Zimmermann, Oswalt, and Lannan is a very solid front 4. I'd then go with a kid in the 5 spot(Ideally Peacock, because he's got the highest upside of the current crop but he might be able to learn some things from Oswalt). But Id be confident with Peacock or Detwiler in that 5 spot. Or even bring Wang back as well, and if he gets beat out, trade him near the end of ST.